'Four' in the Bible

And He will lift up a standard for the nationsAnd assemble the banished ones of Israel,And will gather the dispersed of JudahFrom the four corners of the earth.

Yet gleanings will be left in it like the shaking of an olive tree,Two or three olives on the topmost bough,Four or five on the branches of a fruitful tree,Declares the Lord, the God of Israel.